Modern microwave frequency power amplifiers use Gallium Nitrate (i.e., GaN) transistors to amplify signals. However, the GaN transistors trap and release electronics under various conditions. Where the input signal is a burst of several rapid pulses, the trapping effect causes variable delays in the pulses. A first pulse is subjected to a large phase error. Subsequent pulses experience smaller phase errors until steady state conditions are reached. During idle times between bursts, the trapped electrons are released. The resulting uneven phase errors cause problems in several applications, including radar applications.
It would be desirable to implement amplification phase correction in a pulse burst.